Nitric oxide-related products and myeloperoxidase in bronchoalveolar lavage fluids from patients with ALI activate NF-kappa B in alveolar cells and monocytes.

in Vascular Pharmacology (2005), 43(6), 425-33

An increased production of NO* and peroxynitrite in lungs has been suspected during acute lung injury (ALI) in humans, and recent studies provided evidence for an alveolar production of nitrated compounds ... [more ▼]

An increased production of NO* and peroxynitrite in lungs has been suspected during acute lung injury (ALI) in humans, and recent studies provided evidence for an alveolar production of nitrated compounds. We observed increased concentrations of nitrites/nitrates, nitrated proteins and markers of neutrophil degranulation (myeloperoxidase, elastase and lactoferrine) in the fluids recovered from bronchoalveolar lavage fluids (BALF) of patients with ALI and correlated these changes to the number of neutrophils and the severity of the ALI. We also observed that BALFs stimulated the DNA-binding activity of the nuclear transcription factor kappa B (NF-kappaB) as detected by electrophoretic mobility shift assay in human alveolar cells (A549) and monocytes (THP1). The level of activation of the NF-kappaB-binding activity was correlated to the concentration of nitrated proteins and myeloperoxidase. Furthermore, in vitro studies confirmed that NO*-derived species (peroxynitrite and nitrites) and the neutrophil enzyme myeloperoxidase by themselves increased the activation of NF-kappaB, thereby arguing for an in vivo pathogenetic role of NO*-related products and neutrophil enzymes to human ALI. [less ▲]

Effects of COX-2 inhibitors on ROS produced by Chlamydia pneumoniae-primed human promonocytic cells (THP-1)

in Biochemical and Biophysical Research Communications (2004), 325(4), 1122-1130

Chronic inflammation through foam cells and macrophages is important in atherosclerosis development, and can be considered as therapeutic targets. Cyclooxygenase and NADPH-oxidase were expressed within ... [more ▼]

Chronic inflammation through foam cells and macrophages is important in atherosclerosis development, and can be considered as therapeutic targets. Cyclooxygenase and NADPH-oxidase were expressed within atherosclerotic lesions. Reactive oxygen species produced by NADPH oxidase were found to trigger the cyclooxygenase-2 expression. The effects of preferential COX-2 inhibitors on ROS produced by Chlamydia-primed human monocytes (THP-1 cells) were evaluated by fluorescence, chemiluminescence, oxymetry, and EPR spin trapping. Fluorescence assays showed an increased production of ROS with Chlamydia versus cells primed by 10(-8) M PMA. COX-2 inhibitors inhibited in a dose-dependent manner the luminol-enhanced CL while ibuprofen and diclofenac increased the chemiluminescence response. By EPR spin trapping, COX-2 inhibitors, ibuprofen, and diclofenac, exhibited a dose-dependent inhibiting effect (10 and 100 muM) on the EPR signal appearance. Our cell model combining EPR, chemiluminescence, and oxymetry appeared relevant to study the modulating effects of preferential COX-2 inhibitors on the cell oxidant activity and chronic inflammatory diseases. (C) 2004 Elsevier Inc. All rights reserved. [less ▲]

Propofol scavenges reactive oxygen species and inhibits the protein nitration induced by activated polymorphonuclear neutrophils

in European Journal of Pharmacology (2004), 499(1-2), 29-33

Activated polymorphonuclear neutrophils may damage tissues through the release of biochemical mediators. Among them, peroxynitrite is responsible for hydroxylation reactions and nitration of proteins, or ... [more ▼]

Activated polymorphonuclear neutrophils may damage tissues through the release of biochemical mediators. Among them, peroxynitrite is responsible for hydroxylation reactions and nitration of proteins, or is metabolised into nitrate. We investigated the effect of propofol on the production of reactive oxygen species, the nitration of proteins and the formation of nitrate by activated human polymorphonuclear neutrophils. Propofol dose-dependently inhibited chemiluminescence, nitration of proteins and nitrate production in a concentration range from 10(-3) to 10(-6) mM. A significant correlation was observed between the logarithm of propofol concentration and the intensity of chemiluminescence (r(2) = 0.90), the nitration of proteins (r(2) = 0.67) and the production of nitrate (r(2) = 0.79). Those results are consistent with the scavenging effect of propofol on peroxynitrite and could confer a protective property to propofol in pathological situations involving polymorphonuclear neutrophils activation. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

A European, multicenter, observational study to assess the value of gastric-to-end tidal Pco(2) difference in predicting postoperative complications

in Anesthesia and Analgesia (2004), 99(1), 166-172

Automated online tonometry displays a rapid, semicontinuous measurement of gastric-to-end tidal carbon dioxide (Pr-etCO(2)) as an index of gastrointestinal perfusion during surgery. Its use to predict ... [more ▼]

Automated online tonometry displays a rapid, semicontinuous measurement of gastric-to-end tidal carbon dioxide (Pr-etCO(2)) as an index of gastrointestinal perfusion during surgery. Its use to predict postoperative outcome has not been studied in general surgery patients. We, therefore, studied ASA physical status III-IV patients operated on for elective surgery under general anesthesia and a planned duration of >2 h in a European, multicenter study. As each center was equipped with only 1 tonometric monitor, a randomization was performed if more than one patient was eligible the same day. Patients not monitored with tonometry were assessed only for follow-up. The main outcome measure was the assessment of postoperative functional recovery delay (FRD) on day 8. Among the 290 patients studied, 34% had FRD associated with a longer hospital stay. The most common FRDs were gastrointestinal (45%), infection (39%), and respiratory (35%). In those monitored with tonometry (n = 179), maximum Pr-etCO(2) proved to be the best predictor increasing the probability of FRD from 34% for all patients to 65% at a cut-off of 21 mm Hg (2.8 kPa) (sensitivity 0.27, specificity 0.92, positive predictive value 64%, negative predictive value 70%). We conclude that intraoperative Pr-etCO(2) measurement may be a useful prognostic index of postoperative morbidity. [less ▲]

Actualites en anesthésie-réanimation en chirurgie cardiaque adulte

in Revue Médicale de Liège (2004), 59(1), 35-45

Anesthetic techniques and treatment of cardiac surgery patients have considerably evolved over the past twenty years. The demand for cardiac surgical procedures is increasing. This demand coincides with a ... [more ▼]

Anesthetic techniques and treatment of cardiac surgery patients have considerably evolved over the past twenty years. The demand for cardiac surgical procedures is increasing. This demand coincides with a change in the profile of patients presenting for surgery, requiring modification in perioperative management strategies. Several new anesthetics, related drugs, and technologies have become available in recent years that inevitably have made new approaches with patient management possible. In parallel to these new developments, there have appeared real opportunities to apply novel physiologic and pharmacologic concepts that may redefine our clinical practice. Fast-tracking, which emphasizes the major role of anesthetic management in postoperative outcome, is one such line of investigation. Fast-tracking was first introduced in an attempt to decrease the time to tracheal extubation and reduce expensive time in intensive care unit areas. Large doses of opioids have been clearly identified as a factor in delaying weaning from mechanical ventilatory support after cardiac surgery. Thus, early investigations emphasized the importance of limiting the dose of potent opioid analgesics during the intraoperative period to achieve early recovery. Supplementation with hypnotic drugs allows reduction of the opioid dose, enabling earlier extubation without compromising hemodynamic stability. Fast track cardiac anesthesia (FTCA) is becoming an accepted practice for perioperative management of cardiac surgical patients. FTCA is a key component to successful conduction of fast-track cardiac surgery. Also, analgesia management in cardiac surgery is becoming more important with the establishment of minimally invasive direct coronary artery bypass surgery and fast track management of conventional cardiac surgery patients. [less ▲]

Comparison of different methods for characterizing multi-walled carbon nanotubes

in Colloids and Surfaces A : Physicochemical and Engineering Aspects (2004), 241(1-3), 155-164

Four complementary and independent methods are used to characterize nanotube samples: (i) TEM observation coupled with image analysis, (ii) nitrogen and krypton adsorption isotherm analysis, (iii ... [more ▼]

Four complementary and independent methods are used to characterize nanotube samples: (i) TEM observation coupled with image analysis, (ii) nitrogen and krypton adsorption isotherm analysis, (iii) thermogravimetry and (iv) wide angle X-ray scattering. The methodology is discussed on the basis of two multi-walled carbon nanotube samples produced by the CCVD technique with very different reaction rates. It is shown that the total amount of deposited carbon is larger for the sample produced at the higher rate, that the fraction of nanotubes in the deposited carbon does not seem to be significantly different, but that the crystallinity of the nanotubes wall is larger for the sample produced at the lowest reaction rate. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

Effects of glucocorticoids on the respiratory burst of Chlamydia-primed THP-1 cells.

in Biochemical and Biophysical Research Communications (2004), 318(4), 941-8

We previously observed that the respiratory burst of human monocytes (THP-1 cell line) triggered by phorbol myristate acetate was strongly enhanced by a priming of the cells by Chlamydia pneumoniae ... [more ▼]

We previously observed that the respiratory burst of human monocytes (THP-1 cell line) triggered by phorbol myristate acetate was strongly enhanced by a priming of the cells by Chlamydia pneumoniae [Biochem. Biophys. Res. Commun. 287 (2001) 781]. We describe here the modifications of the responses of Chlamydia-primed THP-1 cells to hydrocortisone (HCT) and methylprednisolone (MPL). HCT and MPL inhibited the production of the cytokines TNFalpha and IL-8. But HCT, which inhibited the respiratory burst in LPS-primed monocytes, paradoxically stimulated the phenomenon in Chlamydia-primed cells; MPL exerted no significant effect. Both glucocorticoids did not significantly modify the triggering effect of Chlamydia on NF-kappaB binding activity. On the expression of p22(phox), a protein subunit of the NADPH oxidase, HCT had an increasing and MPL a decreasing effect. Glucocorticoids thus had unexpected effects on the inflammatory response of Chlamydia-primed monocytes. [less ▲]

Residual cerebral functioning in the vegetative state

in Arco di Giano (2004)

Effects of COX-2 inhibitors on ROS produced by Chlamydia pneumoniae-primed human promonocytic cells (THP-1)

in Biochemical and Biophysical Research Communications (2004), 325(4), 1122-1130

Chronic inflammation through foam cells and macrophages is important in atherosclerosis development, and can be considered as therapeutic targets. Cyclooxygenase and NADPH-oxidase were expressed within ... [more ▼]

Chronic inflammation through foam cells and macrophages is important in atherosclerosis development, and can be considered as therapeutic targets. Cyclooxygenase and NADPH-oxidase were expressed within atherosclerotic lesions. Reactive oxygen species produced by NADPH oxidase were found to trigger the cyclooxygenase-2 expression. The effects of preferential COX-2 inhibitors on ROS produced by Chlamydia-primed human monocytes (THP-1 cells) were evaluated by fluorescence, chemiluminescence, oxymetry, and EPR spin trapping. Fluorescence assays showed an increased production of ROS with Chlamydia versus cells primed by 10 8 M PMA. COX-2 inhibitors inhibited in a dose-dependent manner the luminol-enhanced CL while ibuprofen and diclofenac increased the chemiluminescence response. By EPR spin trapping, COX-2 inhibitors, ibuprofen, and diclofenac, exhibited a dose-dependent inhibiting effect (10 and 100 lM) on the EPR signal appearance. Our cell model combining EPR, chemiluminescence, and oxymetry appeared relevant to study the modulating effects of preferential COX-2 inhibitors on the cell oxidant activity and chronic inflammatory diseases. [less ▲]

Activation of circulating polymorphonuclear neutrophils during exercise-induced muscle damage

in Pflugers Arch – Eur J Physiol (2003, November), 447